A086007 Number of semiprime triples <= n.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3

Offset

1,85

Comments

A semiprime triple is <= n if its least member is <= n;

if a(n-1)<a(n) then (n,n+1,n+2) is a semiprime triple, A086005(a(n))=n+1.

Links

Table of n, a(n) for n=1..102.

Crossrefs

Cf. A001358, A086005.

Sequence in context: A165113 A069903 A331003 * A108582 A345378 A071840

Adjacent sequences: A086004 A086005 A086006 * A086008 A086009 A086010

Keyword

nonn

Author

Reinhard Zumkeller, Jul 07 2003

Status

approved